/* * linux/drivers/serial/s3c2410.c * * Driver for onboard UARTs on the Samsung S3C24XX * * Based on drivers/char/serial.c and drivers/char/21285.c * * Ben Dooks, (c) 2003-2005 Simtec Electronics * http://www.simtec.co.uk/products/SWLINUX/ * * Changelog: * * 22-Jul-2004 BJD Finished off device rewrite * * 21-Jul-2004 BJD Thanks to <herbet@13thfloor.at> for pointing out * problems with baud rate and loss of IR settings. Update * to add configuration via platform_device structure * * 28-Sep-2004 BJD Re-write for the following items * - S3C2410 and S3C2440 serial support * - Power Management support * - Fix console via IrDA devices * - SysReq (Herbert P�tzl) * - Break character handling (Herbert P�tzl) * - spin-lock initialisation (Dimitry Andric) * - added clock control * - updated init code to use platform_device info * * 06-Mar-2005 BJD Add s3c2440 fclk clock source * * 09-Mar-2005 BJD Add s3c2400 support * * 10-Mar-2005 LCVR Changed S3C2410_VA_UART to S3C24XX_VA_UART */ /* Note on 2440 fclk clock source handling * * Whilst it is possible to use the fclk as clock source, the method * of properly switching too/from this is currently un-implemented, so * whichever way is configured at startup is the one that will be used. */ /* Hote on 2410 error handling * * The s3c2410 manual has a love/hate affair with the contents of the * UERSTAT register in the UART blocks, and keeps marking some of the * error bits as reserved. Having checked with the s3c2410x01, * it copes with BREAKs properly, so I am happy to ignore the RESERVED * feature from the latter versions of the manual. * * If it becomes aparrent that latter versions of the 2410 remove these * bits, then action will have to be taken to differentiate the versions * and change the policy on BREAK * * BJD, 04-Nov-2004 */ #include <linux/config.h> #if defined(CONFIG_SERIAL_S3C2410_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) #define SUPPORT_SYSRQ #endif #include <linux/module.h> #include <linux/ioport.h> #include <linux/device.h> #include <linux/init.h> #include <linux/sysrq.h> #include <linux/console.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/serial_core.h> #include <linux/serial.h> #include <linux/delay.h> #include <asm/io.h> #include <asm/irq.h> #include <asm/hardware.h> #include <asm/hardware/clock.h> #include <asm/arch/regs-serial.h> #include <asm/arch/regs-gpio.h> /* structures */ struct s3c24xx_uart_info { char *name; unsigned int type; unsigned int fifosize; unsigned long rx_fifomask; unsigned long rx_fifoshift; unsigned long rx_fifofull; unsigned long tx_fifomask; unsigned long tx_fifoshift; unsigned long tx_fifofull; /* clock source control */ int (*get_clksrc)(struct uart_port *, struct s3c24xx_uart_clksrc *clk); int (*set_clksrc)(struct uart_port *, struct s3c24xx_uart_clksrc *clk); /* uart controls */ int (*reset_port)(struct uart_port *, struct s3c2410_uartcfg *); }; struct s3c24xx_uart_port { unsigned char rx_claimed; unsigned char tx_claimed; struct s3c24xx_uart_info *info; struct s3c24xx_uart_clksrc *clksrc; struct clk *clk; struct clk *baudclk; struct uart_port port; }; /* configuration defines */ #if 0 #if 1 /* send debug to the low-level output routines */ extern void printascii(const char *); static void s3c24xx_serial_dbg(const char *fmt, ...) { va_list va; char buff[256]; va_start(va, fmt); vsprintf(buff, fmt, va); va_end(va); printascii(buff); } #define dbg(x...) s3c24xx_serial_dbg(x) #else #define dbg(x...) printk(KERN_DEBUG "s3c24xx: "); #endif #else /* no debug */ #define dbg(x...) do {} while(0) #endif /* UART name and device definitions */ #define S3C24XX_SERIAL_NAME "ttySAC" #define S3C24XX_SERIAL_DEVFS "tts/" #define S3C24XX_SERIAL_MAJOR 204 #define S3C24XX_SERIAL_MINOR 64 /* conversion functions */ #define s3c24xx_dev_to_port(__dev) (struct uart_port *)dev_get_drvdata(__dev) #define s3c24xx_dev_to_cfg(__dev) (struct s3c2410_uartcfg *)((__dev)->platform_data) /* we can support 3 uarts, but not always use them */ #define NR_PORTS (3) /* port irq numbers */ #define TX_IRQ(port) ((port)->irq + 1) #define RX_IRQ(port) ((port)->irq) /* register access controls */ #define portaddr(port, reg) ((port)->membase + (reg)) #define rd_regb(port, reg) (__raw_readb(portaddr(port, reg))) #define rd_regl(port, reg) (__raw_readl(portaddr(port, reg))) #define wr_regb(port, reg, val) \ do { __raw_writeb(val, portaddr(port, reg)); } while(0) #define wr_regl(port, reg, val) \ do { __raw_writel(val, portaddr(port, reg)); } while(0) /* macros to change one thing to another */ #define tx_enabled(port) ((port)->unused[0]) #define rx_enabled(port) ((port)->unused[1]) /* flag to ignore all characters comming in */ #define RXSTAT_DUMMY_READ (0x10000000) static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port) { return container_of(port, struct s3c24xx_uart_port, port); } /* translate a port to the device name */ static inline const char *s3c24xx_serial_portname(struct uart_port *port) { return to_platform_device(port->dev)->name; } static int s3c24xx_serial_txempty_nofifo(struct uart_port *port) { return (rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE); } static void s3c24xx_serial_rx_enable(struct uart_port *port) { unsigned long flags; unsigned int ucon, ufcon; int count = 10000; spin_lock_irqsave(&port->lock, flags); while (--count && !s3c24xx_serial_txempty_nofifo(port)) udelay(100); ufcon = rd_regl(port, S3C2410_UFCON); ufcon |= S3C2410_UFCON_RESETRX; wr_regl(port, S3C2410_UFCON, ufcon); ucon = rd_regl(port, S3C2410_UCON); ucon |= S3C2410_UCON_RXIRQMODE; wr_regl(port, S3C2410_UCON, ucon); rx_enabled(port) = 1; spin_unlock_irqrestore(&port->lock, flags); } static void s3c24xx_serial_rx_disable(struct uart_port *port) { unsigned long flags; unsigned int ucon; spin_lock_irqsave(&port->lock, flags); ucon = rd_regl(port, S3C2410_UCON); ucon &= ~S3C2410_UCON_RXIRQMODE; wr_regl(port, S3C2410_UCON, ucon); rx_enabled(port) = 0; spin_unlock_irqrestore(&port->lock, flags); } static void s3c24xx_serial_stop_tx(struct uart_port *port) { if (tx_enabled(port)) { disable_irq(TX_IRQ(port)); tx_enabled(port) = 0; if (port->flags & UPF_CONS_FLOW) s3c24xx_serial_rx_enable(port); } } static void s3c24xx_serial_start_tx(struct uart_port *port) { if (!tx_enabled(port)) { if (port->flags & UPF_CONS_FLOW) s3c24xx_serial_rx_disable(port); enable_irq(TX_IRQ(port)); tx_enabled(port) = 1; } } static void s3c24xx_serial_stop_rx(struct uart_port *port) { if (rx_enabled(port)) { dbg("s3c24xx_serial_stop_rx: port=%p\n", port); disable_irq(RX_IRQ(port)); rx_enabled(port) = 0; } } static void s3c24xx_serial_enable_ms(struct uart_port *port) { } static inline struct s3c24xx_uart_info *s3c24xx_port_to_info(struct uart_port *port) { return to_ourport(port)->info; } static inline struct s3c2410_uartcfg *s3c24xx_port_to_cfg(struct uart_port *port) { if (port->dev == NULL) return NULL; return (struct s3c2410_uartcfg *)port->dev->platform_data; } static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport, unsigned long ufstat) { struct s3c24xx_uart_info *info = ourport->info; if (ufstat & info->rx_fifofull) return info->fifosize; return (ufstat & info->rx_fifomask) >> info->rx_fifoshift; } /* ? - where has parity gone?? */ #define S3C2410_UERSTAT_PARITY (0x1000) static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id, struct pt_regs *regs) { struct s3c24xx_uart_port *ourport = dev_id; struct uart_port *port = &ourport->port; struct tty_struct *tty = port->info->tty; unsigned int ufcon, ch, flag, ufstat, uerstat; int max_count = 64; while (max_count-- > 0) { ufcon = rd_regl(port, S3C2410_UFCON); ufstat = rd_regl(port, S3C2410_UFSTAT); if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0) break; if (tty->flip.count >= TTY_FLIPBUF_SIZE) { if (tty->low_latency) tty_flip_buffer_push(tty); /* * If this failed then we will throw away the * bytes but must do so to clear interrupts */ } uerstat = rd_regl(port, S3C2410_UERSTAT); ch = rd_regb(port, S3C2410_URXH); if (port->flags & UPF_CONS_FLOW) { int txe = s3c24xx_serial_txempty_nofifo(port); if (rx_enabled(port)) { if (!txe) { rx_enabled(port) = 0; continue; } } else { if (txe) { ufcon |= S3C2410_UFCON_RESETRX; wr_regl(port, S3C2410_UFCON, ufcon); rx_enabled(port) = 1; goto out; } continue; } } /* insert the character into the buffer */ flag = TTY_NORMAL; port->icount.rx++; if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) { dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n", ch, uerstat); /* check for break */ if (uerstat & S3C2410_UERSTAT_BREAK) { dbg("break!\n"); port->icount.brk++; if (uart_handle_break(port)) goto ignore_char; } if (uerstat & S3C2410_UERSTAT_FRAME) port->icount.frame++; if (uerstat & S3C2410_UERSTAT_OVERRUN) port->icount.overrun++; uerstat &= port->read_status_mask; if (uerstat & S3C2410_UERSTAT_BREAK) flag = TTY_BREAK; else if (uerstat & S3C2410_UERSTAT_PARITY) flag = TTY_PARITY; else if (uerstat & ( S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_OVERRUN)) flag = TTY_FRAME; } if (uart_handle_sysrq_char(port, ch, regs)) goto ignore_char; uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN, ch, flag); ignore_char: continue; } tty_flip_buffer_push(tty); out: return IRQ_HANDLED; } static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id, struct pt_regs *regs) { struct s3c24xx_uart_port *ourport = id; struct uart_port *port = &ourport->port; struct circ_buf *xmit = &port->info->xmit; int count = 256; if (port->x_char) { wr_regb(port, S3C2410_UTXH, port->x_char); port->icount.tx++; port->x_char = 0; goto out; } /* if there isnt anything more to transmit, or the uart is now * stopped, disable the uart and exit */ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { s3c24xx_serial_stop_tx(port); goto out; } /* try and drain the buffer... */ while (!uart_circ_empty(xmit) && count-- > 0) { if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull) break; wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]); xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); port->icount.tx++; } if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(port); if (uart_circ_empty(xmit)) s3c24xx_serial_stop_tx(port); out: return IRQ_HANDLED; } static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT); unsigned long ufcon = rd_regl(port, S3C2410_UFCON); if (ufcon & S3C2410_UFCON_FIFOMODE) { if ((ufstat & info->tx_fifomask) != 0 || (ufstat & info->tx_fifofull)) return 0; return 1; } return s3c24xx_serial_txempty_nofifo(port); } /* no modem control lines */ static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port) { unsigned int umstat = rd_regb(port,S3C2410_UMSTAT); if (umstat & S3C2410_UMSTAT_CTS) return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; else return TIOCM_CAR | TIOCM_DSR; } static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl) { /* todo - possibly remove AFC and do manual CTS */ } static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state) { unsigned long flags; unsigned int ucon; spin_lock_irqsave(&port->lock, flags); ucon = rd_regl(port, S3C2410_UCON); if (break_state) ucon |= S3C2410_UCON_SBREAK; else ucon &= ~S3C2410_UCON_SBREAK; wr_regl(port, S3C2410_UCON, ucon); spin_unlock_irqrestore(&port->lock, flags); } static void s3c24xx_serial_shutdown(struct uart_port *port) { struct s3c24xx_uart_port *ourport = to_ourport(port); if (ourport->tx_claimed) { free_irq(TX_IRQ(port), ourport); tx_enabled(port) = 0; ourport->tx_claimed = 0; } if (ourport->rx_claimed) { free_irq(RX_IRQ(port), ourport); ourport->rx_claimed = 0; rx_enabled(port) = 0; } } static int s3c24xx_serial_startup(struct uart_port *port) { struct s3c24xx_uart_port *ourport = to_ourport(port); int ret; dbg("s3c24xx_serial_startup: port=%p (%08lx,%p)\n", port->mapbase, port->membase); rx_enabled(port) = 1; ret = request_irq(RX_IRQ(port), s3c24xx_serial_rx_chars, 0, s3c24xx_serial_portname(port), ourport); if (ret != 0) { printk(KERN_ERR "cannot get irq %d\n", RX_IRQ(port)); return ret; } ourport->rx_claimed = 1; dbg("requesting tx irq...\n"); tx_enabled(port) = 1; ret = request_irq(TX_IRQ(port), s3c24xx_serial_tx_chars, 0, s3c24xx_serial_portname(port), ourport); if (ret) { printk(KERN_ERR "cannot get irq %d\n", TX_IRQ(port)); goto err; } ourport->tx_claimed = 1; dbg("s3c24xx_serial_startup ok\n"); /* the port reset code should have done the correct * register setup for the port controls */ return ret; err: s3c24xx_serial_shutdown(port); return ret; } /* power power management control */ static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level, unsigned int old) { struct s3c24xx_uart_port *ourport = to_ourport(port); switch (level) { case 3: if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL) clk_disable(ourport->baudclk); clk_disable(ourport->clk); break; case 0: clk_enable(ourport->clk); if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL) clk_enable(ourport->baudclk); break; default: printk(KERN_ERR "s3c24xx_serial: unknown pm %d\n", level); } } /* baud rate calculation * * The UARTs on the S3C2410/S3C2440 can take their clocks from a number * of different sources, including the peripheral clock ("pclk") and an * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk") * with a programmable extra divisor. * * The following code goes through the clock sources, and calculates the * baud clocks (and the resultant actual baud rates) and then tries to * pick the closest one and select that. * */ #define MAX_CLKS (8) static struct s3c24xx_uart_clksrc tmp_clksrc = { .name = "pclk", .min_baud = 0, .max_baud = 0, .divisor = 1, }; static inline int s3c24xx_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); return (info->get_clksrc)(port, c); } static inline int s3c24xx_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); return (info->set_clksrc)(port, c); } struct baud_calc { struct s3c24xx_uart_clksrc *clksrc; unsigned int calc; unsigned int quot; struct clk *src; }; static int s3c24xx_serial_calcbaud(struct baud_calc *calc, struct uart_port *port, struct s3c24xx_uart_clksrc *clksrc, unsigned int baud) { unsigned long rate; calc->src = clk_get(port->dev, clksrc->name); if (calc->src == NULL || IS_ERR(calc->src)) return 0; rate = clk_get_rate(calc->src); rate /= clksrc->divisor; calc->clksrc = clksrc; calc->quot = (rate + (8 * baud)) / (16 * baud); calc->calc = (rate / (calc->quot * 16)); calc->quot--; return 1; } static unsigned int s3c24xx_serial_getclk(struct uart_port *port, struct s3c24xx_uart_clksrc **clksrc, struct clk **clk, unsigned int baud) { struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port); struct s3c24xx_uart_clksrc *clkp; struct baud_calc res[MAX_CLKS]; struct baud_calc *resptr, *best, *sptr; int i; clkp = cfg->clocks; best = NULL; if (cfg->clocks_size < 2) { if (cfg->clocks_size == 0) clkp = &tmp_clksrc; /* check to see if we're sourcing fclk, and if so we're * going to have to update the clock source */ if (strcmp(clkp->name, "fclk") == 0) { struct s3c24xx_uart_clksrc src; s3c24xx_serial_getsource(port, &src); /* check that the port already using fclk, and if * not, then re-select fclk */ if (strcmp(src.name, clkp->name) == 0) { s3c24xx_serial_setsource(port, clkp); s3c24xx_serial_getsource(port, &src); } clkp->divisor = src.divisor; } s3c24xx_serial_calcbaud(res, port, clkp, baud); best = res; resptr = best + 1; } else { resptr = res; for (i = 0; i < cfg->clocks_size; i++, clkp++) { if (s3c24xx_serial_calcbaud(resptr, port, clkp, baud)) resptr++; } } /* ok, we now need to select the best clock we found */ if (!best) { unsigned int deviation = (1<<30)|((1<<30)-1); int calc_deviation; for (sptr = res; sptr < resptr; sptr++) { printk(KERN_DEBUG "found clk %p (%s) quot %d, calc %d\n", sptr->clksrc, sptr->clksrc->name, sptr->quot, sptr->calc); calc_deviation = baud - sptr->calc; if (calc_deviation < 0) calc_deviation = -calc_deviation; if (calc_deviation < deviation) { best = sptr; deviation = calc_deviation; } } printk(KERN_DEBUG "best %p (deviation %d)\n", best, deviation); } printk(KERN_DEBUG "selected clock %p (%s) quot %d, calc %d\n", best->clksrc, best->clksrc->name, best->quot, best->calc); /* store results to pass back */ *clksrc = best->clksrc; *clk = best->src; return best->quot; } static void s3c24xx_serial_set_termios(struct uart_port *port, struct termios *termios, struct termios *old) { struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port); struct s3c24xx_uart_port *ourport = to_ourport(port); struct s3c24xx_uart_clksrc *clksrc = NULL; struct clk *clk = NULL; unsigned long flags; unsigned int baud, quot; unsigned int ulcon; unsigned int umcon; /* * We don't support modem control lines. */ termios->c_cflag &= ~(HUPCL | CMSPAR); termios->c_cflag |= CLOCAL; /* * Ask the core to calculate the divisor for us. */ baud = uart_get_baud_rate(port, termios, old, 0, 115200*8); if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) quot = port->custom_divisor; else quot = s3c24xx_serial_getclk(port, &clksrc, &clk, baud); /* check to see if we need to change clock source */ if (ourport->clksrc != clksrc || ourport->baudclk != clk) { s3c24xx_serial_setsource(port, clksrc); if (ourport->baudclk != NULL && !IS_ERR(ourport->baudclk)) { clk_disable(ourport->baudclk); clk_unuse(ourport->baudclk); ourport->baudclk = NULL; } clk_use(clk); clk_enable(clk); ourport->clksrc = clksrc; ourport->baudclk = clk; } switch (termios->c_cflag & CSIZE) { case CS5: dbg("config: 5bits/char\n"); ulcon = S3C2410_LCON_CS5; break; case CS6: dbg("config: 6bits/char\n"); ulcon = S3C2410_LCON_CS6; break; case CS7: dbg("config: 7bits/char\n"); ulcon = S3C2410_LCON_CS7; break; case CS8: default: dbg("config: 8bits/char\n"); ulcon = S3C2410_LCON_CS8; break; } /* preserve original lcon IR settings */ ulcon |= (cfg->ulcon & S3C2410_LCON_IRM); if (termios->c_cflag & CSTOPB) ulcon |= S3C2410_LCON_STOPB; umcon = (termios->c_cflag & CRTSCTS) ? S3C2410_UMCOM_AFC : 0; if (termios->c_cflag & PARENB) { if (termios->c_cflag & PARODD) ulcon |= S3C2410_LCON_PODD; else ulcon |= S3C2410_LCON_PEVEN; } else { ulcon |= S3C2410_LCON_PNONE; } spin_lock_irqsave(&port->lock, flags); dbg("setting ulcon to %08x, brddiv to %d\n", ulcon, quot); wr_regl(port, S3C2410_ULCON, ulcon); wr_regl(port, S3C2410_UBRDIV, quot); wr_regl(port, S3C2410_UMCON, umcon); dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n", rd_regl(port, S3C2410_ULCON), rd_regl(port, S3C2410_UCON), rd_regl(port, S3C2410_UFCON)); /* * Update the per-port timeout. */ uart_update_timeout(port, termios->c_cflag, baud); /* * Which character status flags are we interested in? */ port->read_status_mask = S3C2410_UERSTAT_OVERRUN; if (termios->c_iflag & INPCK) port->read_status_mask |= S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_PARITY; /* * Which character status flags should we ignore? */ port->ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN; if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR) port->ignore_status_mask |= S3C2410_UERSTAT_FRAME; /* * Ignore all characters if CREAD is not set. */ if ((termios->c_cflag & CREAD) == 0) port->ignore_status_mask |= RXSTAT_DUMMY_READ; spin_unlock_irqrestore(&port->lock, flags); } static const char *s3c24xx_serial_type(struct uart_port *port) { switch (port->type) { case PORT_S3C2410: return "S3C2410"; case PORT_S3C2440: return "S3C2440"; default: return NULL; } } #define MAP_SIZE (0x100) static void s3c24xx_serial_release_port(struct uart_port *port) { release_mem_region(port->mapbase, MAP_SIZE); } static int s3c24xx_serial_request_port(struct uart_port *port) { const char *name = s3c24xx_serial_portname(port); return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY; } static void s3c24xx_serial_config_port(struct uart_port *port, int flags) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); if (flags & UART_CONFIG_TYPE && s3c24xx_serial_request_port(port) == 0) port->type = info->type; } /* * verify the new serial_struct (for TIOCSSERIAL). */ static int s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); if (ser->type != PORT_UNKNOWN && ser->type != info->type) return -EINVAL; return 0; } #ifdef CONFIG_SERIAL_S3C2410_CONSOLE static struct console s3c24xx_serial_console; #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console #else #define S3C24XX_SERIAL_CONSOLE NULL #endif static struct uart_ops s3c24xx_serial_ops = { .pm = s3c24xx_serial_pm, .tx_empty = s3c24xx_serial_tx_empty, .get_mctrl = s3c24xx_serial_get_mctrl, .set_mctrl = s3c24xx_serial_set_mctrl, .stop_tx = s3c24xx_serial_stop_tx, .start_tx = s3c24xx_serial_start_tx, .stop_rx = s3c24xx_serial_stop_rx, .enable_ms = s3c24xx_serial_enable_ms, .break_ctl = s3c24xx_serial_break_ctl, .startup = s3c24xx_serial_startup, .shutdown = s3c24xx_serial_shutdown, .set_termios = s3c24xx_serial_set_termios, .type = s3c24xx_serial_type, .release_port = s3c24xx_serial_release_port, .request_port = s3c24xx_serial_request_port, .config_port = s3c24xx_serial_config_port, .verify_port = s3c24xx_serial_verify_port, }; static struct uart_driver s3c24xx_uart_drv = { .owner = THIS_MODULE, .dev_name = "s3c2410_serial", .nr = 3, .cons = S3C24XX_SERIAL_CONSOLE, .driver_name = S3C24XX_SERIAL_NAME, .devfs_name = S3C24XX_SERIAL_DEVFS, .major = S3C24XX_SERIAL_MAJOR, .minor = S3C24XX_SERIAL_MINOR, }; static struct s3c24xx_uart_port s3c24xx_serial_ports[NR_PORTS] = { [0] = { .port = { .lock = SPIN_LOCK_UNLOCKED, .iotype = UPIO_MEM, .irq = IRQ_S3CUART_RX0, .uartclk = 0, .fifosize = 16, .ops = &s3c24xx_serial_ops, .flags = UPF_BOOT_AUTOCONF, .line = 0, } }, [1] = { .port = { .lock = SPIN_LOCK_UNLOCKED, .iotype = UPIO_MEM, .irq = IRQ_S3CUART_RX1, .uartclk = 0, .fifosize = 16, .ops = &s3c24xx_serial_ops, .flags = UPF_BOOT_AUTOCONF, .line = 1, } }, #if NR_PORTS > 2 [2] = { .port = { .lock = SPIN_LOCK_UNLOCKED, .iotype = UPIO_MEM, .irq = IRQ_S3CUART_RX2, .uartclk = 0, .fifosize = 16, .ops = &s3c24xx_serial_ops, .flags = UPF_BOOT_AUTOCONF, .line = 2, } } #endif }; /* s3c24xx_serial_resetport * * wrapper to call the specific reset for this port (reset the fifos * and the settings) */ static inline int s3c24xx_serial_resetport(struct uart_port * port, struct s3c2410_uartcfg *cfg) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); return (info->reset_port)(port, cfg); } /* s3c24xx_serial_init_port * * initialise a single serial port from the platform device given */ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport, struct s3c24xx_uart_info *info, struct platform_device *platdev) { struct uart_port *port = &ourport->port; struct s3c2410_uartcfg *cfg; struct resource *res; dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev); if (platdev == NULL) return -ENODEV; cfg = s3c24xx_dev_to_cfg(&platdev->dev); if (port->mapbase != 0) return 0; if (cfg->hwport > 3) return -EINVAL; /* setup info for port */ port->dev = &platdev->dev; ourport->info = info; /* copy the info in from provided structure */ ourport->port.fifosize = info->fifosize; dbg("s3c24xx_serial_init_port: %p (hw %d)...\n", port, cfg->hwport); port->uartclk = 1; if (cfg->uart_flags & UPF_CONS_FLOW) { dbg("s3c24xx_serial_init_port: enabling flow control\n"); port->flags |= UPF_CONS_FLOW; } /* sort our the physical and virtual addresses for each UART */ res = platform_get_resource(platdev, IORESOURCE_MEM, 0); if (res == NULL) { printk(KERN_ERR "failed to find memory resource for uart\n"); return -EINVAL; } dbg("resource %p (%lx..%lx)\n", res, res->start, res->end); port->mapbase = res->start; port->membase = S3C24XX_VA_UART + (res->start - S3C2410_PA_UART); port->irq = platform_get_irq(platdev, 0); ourport->clk = clk_get(&platdev->dev, "uart"); if (ourport->clk != NULL && !IS_ERR(ourport->clk)) clk_use(ourport->clk); dbg("port: map=%08x, mem=%08x, irq=%d, clock=%ld\n", port->mapbase, port->membase, port->irq, port->uartclk); /* reset the fifos (and setup the uart) */ s3c24xx_serial_resetport(port, cfg); return 0; } /* Device driver serial port probe */ static int probe_index = 0; static int s3c24xx_serial_probe(struct device *_dev, struct s3c24xx_uart_info *info) { struct s3c24xx_uart_port *ourport; struct platform_device *dev = to_platform_device(_dev); int ret; dbg("s3c24xx_serial_probe(%p, %p) %d\n", _dev, info, probe_index); ourport = &s3c24xx_serial_ports[probe_index]; probe_index++; dbg("%s: initialising port %p...\n", __FUNCTION__, ourport); ret = s3c24xx_serial_init_port(ourport, info, dev); if (ret < 0) goto probe_err; dbg("%s: adding port\n", __FUNCTION__); uart_add_one_port(&s3c24xx_uart_drv, &ourport->port); dev_set_drvdata(_dev, &ourport->port); return 0; probe_err: return ret; } static int s3c24xx_serial_remove(struct device *_dev) { struct uart_port *port = s3c24xx_dev_to_port(_dev); if (port) uart_remove_one_port(&s3c24xx_uart_drv, port); return 0; } /* UART power management code */ #ifdef CONFIG_PM static int s3c24xx_serial_suspend(struct device *dev, pm_message_t state, u32 level) { struct uart_port *port = s3c24xx_dev_to_port(dev); if (port && level == SUSPEND_DISABLE) uart_suspend_port(&s3c24xx_uart_drv, port); return 0; } static int s3c24xx_serial_resume(struct device *dev, u32 level) { struct uart_port *port = s3c24xx_dev_to_port(dev); struct s3c24xx_uart_port *ourport = to_ourport(port); if (port && level == RESUME_ENABLE) { clk_enable(ourport->clk); s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port)); clk_disable(ourport->clk); uart_resume_port(&s3c24xx_uart_drv, port); } return 0; } #else #define s3c24xx_serial_suspend NULL #define s3c24xx_serial_resume NULL #endif static int s3c24xx_serial_init(struct device_driver *drv, struct s3c24xx_uart_info *info) { dbg("s3c24xx_serial_init(%p,%p)\n", drv, info); return driver_register(drv); } /* now comes the code to initialise either the s3c2410 or s3c2440 serial * port information */ /* cpu specific variations on the serial port support */ #ifdef CONFIG_CPU_S3C2400 static int s3c2400_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { clk->divisor = 1; clk->name = "pclk"; return 0; } static int s3c2400_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { return 0; } static int s3c2400_serial_resetport(struct uart_port *port, struct s3c2410_uartcfg *cfg) { dbg("s3c2400_serial_resetport: port=%p (%08lx), cfg=%p\n", port, port->mapbase, cfg); wr_regl(port, S3C2410_UCON, cfg->ucon); wr_regl(port, S3C2410_ULCON, cfg->ulcon); /* reset both fifos */ wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH); wr_regl(port, S3C2410_UFCON, cfg->ufcon); return 0; } static struct s3c24xx_uart_info s3c2400_uart_inf = { .name = "Samsung S3C2400 UART", .type = PORT_S3C2400, .fifosize = 16, .rx_fifomask = S3C2410_UFSTAT_RXMASK, .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT, .rx_fifofull = S3C2410_UFSTAT_RXFULL, .tx_fifofull = S3C2410_UFSTAT_TXFULL, .tx_fifomask = S3C2410_UFSTAT_TXMASK, .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT, .get_clksrc = s3c2400_serial_getsource, .set_clksrc = s3c2400_serial_setsource, .reset_port = s3c2400_serial_resetport, }; static int s3c2400_serial_probe(struct device *dev) { return s3c24xx_serial_probe(dev, &s3c2400_uart_inf); } static struct device_driver s3c2400_serial_drv = { .name = "s3c2400-uart", .owner = THIS_MODULE, .bus = &platform_bus_type, .probe = s3c2400_serial_probe, .remove = s3c24xx_serial_remove, .suspend = s3c24xx_serial_suspend, .resume = s3c24xx_serial_resume, }; static inline int s3c2400_serial_init(void) { return s3c24xx_serial_init(&s3c2400_serial_drv, &s3c2400_uart_inf); } static inline void s3c2400_serial_exit(void) { driver_unregister(&s3c2400_serial_drv); } #define s3c2400_uart_inf_at &s3c2400_uart_inf #else static inline int s3c2400_serial_init(void) { return 0; } static inline void s3c2400_serial_exit(void) { } #define s3c2400_uart_inf_at NULL #endif /* CONFIG_CPU_S3C2400 */ /* S3C2410 support */ #ifdef CONFIG_CPU_S3C2410 static int s3c2410_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { unsigned long ucon = rd_regl(port, S3C2410_UCON); if (strcmp(clk->name, "uclk") == 0) ucon |= S3C2410_UCON_UCLK; else ucon &= ~S3C2410_UCON_UCLK; wr_regl(port, S3C2410_UCON, ucon); return 0; } static int s3c2410_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { unsigned long ucon = rd_regl(port, S3C2410_UCON); clk->divisor = 1; clk->name = (ucon & S3C2410_UCON_UCLK) ? "uclk" : "pclk"; return 0; } static int s3c2410_serial_resetport(struct uart_port *port, struct s3c2410_uartcfg *cfg) { dbg("s3c2410_serial_resetport: port=%p (%08lx), cfg=%p\n", port, port->mapbase, cfg); wr_regl(port, S3C2410_UCON, cfg->ucon); wr_regl(port, S3C2410_ULCON, cfg->ulcon); /* reset both fifos */ wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH); wr_regl(port, S3C2410_UFCON, cfg->ufcon); return 0; } static struct s3c24xx_uart_info s3c2410_uart_inf = { .name = "Samsung S3C2410 UART", .type = PORT_S3C2410, .fifosize = 16, .rx_fifomask = S3C2410_UFSTAT_RXMASK, .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT, .rx_fifofull = S3C2410_UFSTAT_RXFULL, .tx_fifofull = S3C2410_UFSTAT_TXFULL, .tx_fifomask = S3C2410_UFSTAT_TXMASK, .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT, .get_clksrc = s3c2410_serial_getsource, .set_clksrc = s3c2410_serial_setsource, .reset_port = s3c2410_serial_resetport, }; /* device management */ static int s3c2410_serial_probe(struct device *dev) { return s3c24xx_serial_probe(dev, &s3c2410_uart_inf); } static struct device_driver s3c2410_serial_drv = { .name = "s3c2410-uart", .owner = THIS_MODULE, .bus = &platform_bus_type, .probe = s3c2410_serial_probe, .remove = s3c24xx_serial_remove, .suspend = s3c24xx_serial_suspend, .resume = s3c24xx_serial_resume, }; static inline int s3c2410_serial_init(void) { return s3c24xx_serial_init(&s3c2410_serial_drv, &s3c2410_uart_inf); } static inline void s3c2410_serial_exit(void) { driver_unregister(&s3c2410_serial_drv); } #define s3c2410_uart_inf_at &s3c2410_uart_inf #else static inline int s3c2410_serial_init(void) { return 0; } static inline void s3c2410_serial_exit(void) { } #define s3c2410_uart_inf_at NULL #endif /* CONFIG_CPU_S3C2410 */ #ifdef CONFIG_CPU_S3C2440 static int s3c2440_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { unsigned long ucon = rd_regl(port, S3C2410_UCON); // todo - proper fclk<>nonfclk switch // ucon &= ~S3C2440_UCON_CLKMASK; if (strcmp(clk->name, "uclk") == 0) ucon |= S3C2440_UCON_UCLK; else if (strcmp(clk->name, "pclk") == 0) ucon |= S3C2440_UCON_PCLK; else if (strcmp(clk->name, "fclk") == 0) ucon |= S3C2440_UCON_FCLK; else { printk(KERN_ERR "unknown clock source %s\n", clk->name); return -EINVAL; } wr_regl(port, S3C2410_UCON, ucon); return 0; } static int s3c2440_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *clk) { unsigned long ucon = rd_regl(port, S3C2410_UCON); unsigned long ucon0, ucon1, ucon2; switch (ucon & S3C2440_UCON_CLKMASK) { case S3C2440_UCON_UCLK: clk->divisor = 1; clk->name = "uclk"; break; case S3C2440_UCON_PCLK: case S3C2440_UCON_PCLK2: clk->divisor = 1; clk->name = "pclk"; break; case S3C2440_UCON_FCLK: /* the fun of calculating the uart divisors on * the s3c2440 */ ucon0 = __raw_readl(S3C24XX_VA_UART0 + S3C2410_UCON); ucon1 = __raw_readl(S3C24XX_VA_UART1 + S3C2410_UCON); ucon2 = __raw_readl(S3C24XX_VA_UART2 + S3C2410_UCON); printk("ucons: %08lx, %08lx, %08lx\n", ucon0, ucon1, ucon2); ucon0 &= S3C2440_UCON0_DIVMASK; ucon1 &= S3C2440_UCON1_DIVMASK; ucon2 &= S3C2440_UCON2_DIVMASK; if (ucon0 != 0) { clk->divisor = ucon0 >> S3C2440_UCON_DIVSHIFT; clk->divisor += 6; } else if (ucon1 != 0) { clk->divisor = ucon1 >> S3C2440_UCON_DIVSHIFT; clk->divisor += 21; } else if (ucon2 != 0) { clk->divisor = ucon2 >> S3C2440_UCON_DIVSHIFT; clk->divisor += 36; } else { /* manual calims 44, seems to be 9 */ clk->divisor = 9; } clk->name = "fclk"; break; } return 0; } static int s3c2440_serial_resetport(struct uart_port *port, struct s3c2410_uartcfg *cfg) { unsigned long ucon = rd_regl(port, S3C2410_UCON); dbg("s3c2440_serial_resetport: port=%p (%08lx), cfg=%p\n", port, port->mapbase, cfg); /* ensure we don't change the clock settings... */ ucon &= (S3C2440_UCON0_DIVMASK | (3<<10)); wr_regl(port, S3C2410_UCON, ucon | cfg->ucon); wr_regl(port, S3C2410_ULCON, cfg->ulcon); /* reset both fifos */ wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH); wr_regl(port, S3C2410_UFCON, cfg->ufcon); return 0; } static struct s3c24xx_uart_info s3c2440_uart_inf = { .name = "Samsung S3C2440 UART", .type = PORT_S3C2440, .fifosize = 64, .rx_fifomask = S3C2440_UFSTAT_RXMASK, .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT, .rx_fifofull = S3C2440_UFSTAT_RXFULL, .tx_fifofull = S3C2440_UFSTAT_TXFULL, .tx_fifomask = S3C2440_UFSTAT_TXMASK, .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT, .get_clksrc = s3c2440_serial_getsource, .set_clksrc = s3c2440_serial_setsource, .reset_port = s3c2440_serial_resetport, }; /* device management */ static int s3c2440_serial_probe(struct device *dev) { dbg("s3c2440_serial_probe: dev=%p\n", dev); return s3c24xx_serial_probe(dev, &s3c2440_uart_inf); } static struct device_driver s3c2440_serial_drv = { .name = "s3c2440-uart", .owner = THIS_MODULE, .bus = &platform_bus_type, .probe = s3c2440_serial_probe, .remove = s3c24xx_serial_remove, .suspend = s3c24xx_serial_suspend, .resume = s3c24xx_serial_resume, }; static inline int s3c2440_serial_init(void) { return s3c24xx_serial_init(&s3c2440_serial_drv, &s3c2440_uart_inf); } static inline void s3c2440_serial_exit(void) { driver_unregister(&s3c2440_serial_drv); } #define s3c2440_uart_inf_at &s3c2440_uart_inf #else static inline int s3c2440_serial_init(void) { return 0; } static inline void s3c2440_serial_exit(void) { } #define s3c2440_uart_inf_at NULL #endif /* CONFIG_CPU_S3C2440 */ /* module initialisation code */ static int __init s3c24xx_serial_modinit(void) { int ret; ret = uart_register_driver(&s3c24xx_uart_drv); if (ret < 0) { printk(KERN_ERR "failed to register UART driver\n"); return -1; } s3c2400_serial_init(); s3c2410_serial_init(); s3c2440_serial_init(); return 0; } static void __exit s3c24xx_serial_modexit(void) { s3c2400_serial_exit(); s3c2410_serial_exit(); s3c2440_serial_exit(); uart_unregister_driver(&s3c24xx_uart_drv); } module_init(s3c24xx_serial_modinit); module_exit(s3c24xx_serial_modexit); /* Console code */ #ifdef CONFIG_SERIAL_S3C2410_CONSOLE static struct uart_port *cons_uart; static int s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon) { struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); unsigned long ufstat, utrstat; if (ufcon & S3C2410_UFCON_FIFOMODE) { /* fifo mode - check ammount of data in fifo registers... */ ufstat = rd_regl(port, S3C2410_UFSTAT); return (ufstat & info->tx_fifofull) ? 0 : 1; } /* in non-fifo mode, we go and use the tx buffer empty */ utrstat = rd_regl(port, S3C2410_UTRSTAT); return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0; } static void s3c24xx_serial_console_write(struct console *co, const char *s, unsigned int count) { int i; unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON); for (i = 0; i < count; i++) { while (!s3c24xx_serial_console_txrdy(cons_uart, ufcon)) barrier(); wr_regb(cons_uart, S3C2410_UTXH, s[i]); if (s[i] == '\n') { while (!s3c24xx_serial_console_txrdy(cons_uart, ufcon)) barrier(); wr_regb(cons_uart, S3C2410_UTXH, '\r'); } } } static void __init s3c24xx_serial_get_options(struct uart_port *port, int *baud, int *parity, int *bits) { struct s3c24xx_uart_clksrc clksrc; struct clk *clk; unsigned int ulcon; unsigned int ucon; unsigned int ubrdiv; unsigned long rate; ulcon = rd_regl(port, S3C2410_ULCON); ucon = rd_regl(port, S3C2410_UCON); ubrdiv = rd_regl(port, S3C2410_UBRDIV); dbg("s3c24xx_serial_get_options: port=%p\n" "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n", port, ulcon, ucon, ubrdiv); if ((ucon & 0xf) != 0) { /* consider the serial port configured if the tx/rx mode set */ switch (ulcon & S3C2410_LCON_CSMASK) { case S3C2410_LCON_CS5: *bits = 5; break; case S3C2410_LCON_CS6: *bits = 6; break; case S3C2410_LCON_CS7: *bits = 7; break; default: case S3C2410_LCON_CS8: *bits = 8; break; } switch (ulcon & S3C2410_LCON_PMASK) { case S3C2410_LCON_PEVEN: *parity = 'e'; break; case S3C2410_LCON_PODD: *parity = 'o'; break; case S3C2410_LCON_PNONE: default: *parity = 'n'; } /* now calculate the baud rate */ s3c24xx_serial_getsource(port, &clksrc); clk = clk_get(port->dev, clksrc.name); if (!IS_ERR(clk) && clk != NULL) rate = clk_get_rate(clk) / clksrc.divisor; else rate = 1; *baud = rate / ( 16 * (ubrdiv + 1)); dbg("calculated baud %d\n", *baud); } } /* s3c24xx_serial_init_ports * * initialise the serial ports from the machine provided initialisation * data. */ static int s3c24xx_serial_init_ports(struct s3c24xx_uart_info *info) { struct s3c24xx_uart_port *ptr = s3c24xx_serial_ports; struct platform_device **platdev_ptr; int i; dbg("s3c24xx_serial_init_ports: initialising ports...\n"); platdev_ptr = s3c24xx_uart_devs; for (i = 0; i < NR_PORTS; i++, ptr++, platdev_ptr++) { s3c24xx_serial_init_port(ptr, info, *platdev_ptr); } return 0; } static int __init s3c24xx_serial_console_setup(struct console *co, char *options) { struct uart_port *port; int baud = 9600; int bits = 8; int parity = 'n'; int flow = 'n'; dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n", co, co->index, options); /* is this a valid port */ if (co->index == -1 || co->index >= NR_PORTS) co->index = 0; port = &s3c24xx_serial_ports[co->index].port; /* is the port configured? */ if (port->mapbase == 0x0) { co->index = 0; port = &s3c24xx_serial_ports[co->index].port; } cons_uart = port; dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index); /* * Check whether an invalid uart number has been specified, and * if so, search for the first available port that does have * console support. */ if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); else s3c24xx_serial_get_options(port, &baud, &parity, &bits); dbg("s3c24xx_serial_console_setup: baud %d\n", baud); return uart_set_options(port, co, baud, parity, bits, flow); } /* s3c24xx_serial_initconsole * * initialise the console from one of the uart drivers */ static struct console s3c24xx_serial_console = { .name = S3C24XX_SERIAL_NAME, .device = uart_console_device, .flags = CON_PRINTBUFFER, .index = -1, .write = s3c24xx_serial_console_write, .setup = s3c24xx_serial_console_setup }; static int s3c24xx_serial_initconsole(void) { struct s3c24xx_uart_info *info; struct platform_device *dev = s3c24xx_uart_devs[0]; dbg("s3c24xx_serial_initconsole\n"); /* select driver based on the cpu */ if (dev == NULL) { printk(KERN_ERR "s3c24xx: no devices for console init\n"); return 0; } if (strcmp(dev->name, "s3c2400-uart") == 0) { info = s3c2400_uart_inf_at; } else if (strcmp(dev->name, "s3c2410-uart") == 0) { info = s3c2410_uart_inf_at; } else if (strcmp(dev->name, "s3c2440-uart") == 0) { info = s3c2440_uart_inf_at; } else { printk(KERN_ERR "s3c24xx: no driver for %s\n", dev->name); return 0; } if (info == NULL) { printk(KERN_ERR "s3c24xx: no driver for console\n"); return 0; } s3c24xx_serial_console.data = &s3c24xx_uart_drv; s3c24xx_serial_init_ports(info); register_console(&s3c24xx_serial_console); return 0; } console_initcall(s3c24xx_serial_initconsole); #endif /* CONFIG_SERIAL_S3C2410_CONSOLE */ MODULE_LICENSE("GPL"); MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); MODULE_DESCRIPTION("Samsung S3C2410/S3C2440 Serial port driver");